Genetics: The Study of Heredity Flashcards

Key Concepts in Genetics

• Traits: Distinct physical characteristics that can be observed in organisms.
• Heredity: The transmission of traits from parents to their offspring, a fundamental principle of genetics.
• Genetics: The scientific discipline focused on the study of heredity and the variation of inherited characteristics.

Historical Context

• Gregor Mendel: Recognized as the Father of Genetics for his pioneering work on inheritance patterns in pea plants, laying the groundwork for modern genetics.

Molecular Basis of Genetics

• Chromosomes: Structures located in the cell that contain DNA; key components for genetic inheritance.
• Gene: A specific segment of DNA that encodes a particular trait or characteristic, arranged in a specific sequence or pattern.
• Alleles: Various forms of a gene that can exist at a given locus on a chromosome.

Alleles and Inheritance

• Dominant Allele: An allele that masks the effect of a recessive allele in a heterozygous condition.
• Recessive Allele: An allele whose effects are hidden or masked by a dominant allele; expressed only when homozygous.
• Homozygous: A genotype consisting of two identical alleles for a specific trait.
• Heterozygous: A genotype with two different alleles for a particular trait.

Genetic Composition

• Genotype: The genetic constitution of an organism, representing the alleles present.
• Phenotype: The observable physical or biochemical characteristics of an organism, determined by both genotype and environment.

Tools for Genetic Analysis

• Punnett Square: A diagrammatic tool used to predict the outcome of genetic crosses by showing all possible allele combinations.
• Codominance: A genetic scenario where neither allele is dominant or recessive, leading to the expression of both traits in the phenotype.

Theoretical Framework

• Chromosome Theory of Inheritance: The principle that genes are located on chromosomes and are passed to offspring through these structures during reproduction.

Biological Processes

• Reproduction: The biological process by which new individuals are generated from parent organisms, ensuring the continuation of species.
• Zygote: The initial cell formed when a sperm cell fertilizes an egg cell, representing the earliest stage of development.
• Meiosis: A special type of cell division that reduces the chromosome number by half, crucial for the formation of gametes.

Nucleic Acids and Their Functions

• RNA (Ribonucleic Acid): A vital molecule involved in various biological roles, especially in coding, decoding, regulation, and expression of genes.
• mRNA (Messenger RNA): A form of RNA that carries the genetic information copied from DNA to the ribosome for protein synthesis.
• tRNA (Transfer RNA): A type of RNA that transports amino acids to the ribosome, where they are assembled into proteins.

Genetic Variability

• Mutation: Any permanent alteration in the DNA sequence of a gene or chromosome, which can lead to changes in traits and may contribute to genetic diversity.